Question

For the transistor circuit shown, $\beta =100$ and voltage drop between emitter and base is $0.7V$. The value of $V_{CE}$ will be

• A. $10V$
• B. $5V$
• C. $13V$
• D. $0V$

Answer 1

The correct option is C $13V$

Let us redraw the circuit diagram to denote the potential at different points and the current through different segments.


Here $i_c$ is the collector current while $i_b$ is the base current. Also we have assumed that potential at points A and B is 0.
The net potential drop across any loop must be zero.
Writing the voltage equation for the loop consisting of the resistance of $8.6k\Omega$
$5-8.6\times {10}^3\times i_b-0.7=0$ ---(1)
Also, $\beta =\frac{i_c}{i_b}=100$ ---(2)
Writing the balance equation for the loop consisting of the resistance of $100\Omega$
$18-100\times i_c-V_{CE}=0$ -----------(3)

From equation (1),
$i_b=0.5\times {10}^{-3}A$
From equation (2),
$i_c=0.05A$
and from equation (3),
$V_{CE}=13V$